1. Technical Field
The present disclosure generally relates to circuit design and in particular, to phased lock loop circuits.
2. Description of the Related Art
Phase locked loops (PLLs) are circuit building blocks commonly used in microelectronic components that require signal processing. Such components include, for example, radio transmitters and receivers that provide wireless communication functions in mobile computing devices, e.g., smart phones. Another application of phase locked loops is in clock generators for microprocessors. A phased locked loop is constructed as a negative feedback control system in which an output signal, the feedback signal, is generated from an input reference signal, such that the output signal maintains a certain phase relationship with the reference signal. A phase detector and a voltage-controlled oscillator cooperate to compare and lock the phases of the feedback and reference signals, according to the desired phase relationship.